Cave iconography is limited to three basic themes: animals, human figures and signs. We do not find representations of the landscape outside, nor of species of plants. The bestiary is the reflection of the fauna as the people of the Palaeolithic knew it, but is not representative of their dietary habits.

There are some 6,000 representations of animals at Lascaux. Images of horses are by far the most numerous, followed by equal numbers of stags and aurochs, and then by ibexes and bison. The few representations of carnivores, such as bears and felines, are found in the furthest corners of the cave – a characteristic shared with other sites. Carnivores keep a very low profile in the real world, and this is also true in the cave. The painters used various methods to render this – by depicting them in the innermost depths, by placing them in pre-existing drawings (such as the bear hidden in the ventral region of a large aurochs), by making very minimalist drawings and by disguising them. This is a hypothesis that is often evoked in the case of the Unicorn.

Sanctuaries in which a human figure appears more than once are rare indeed, and Lascaux is no exception. It contains one single image of a anthropomorphic figure, in the Shaft Scene. More frequently, the graphic rendering of the human figure is limited to one anatomical segment: negative or positive hand images and representations of the female – and much less often, the male – sex. Human images can also take on a cryptic aspect, with the substitution of animal parts for human ones, including horns, antlers, hooves, bird heads, and so on.
There are two types of signs. The first are simple shapes (dots, lines, streaks, etc.) and the second are more elaborate signs that are only found at a few sites (branching signs, quadrangular or pentagonal shapes, and so on).